The present invention utilizes phenomena associated with angular momentum conservation of solid bodies in a novel and especially efficient way so as to create a stepless transmission capable of infinitely varying torque and angular velocity, within the limits of a particular device, and the process of transmitting power in the form of a time-rate-of-change of rotational kinetic energy. If insufficient torque is available for a given load demand, additional output torque is generated by the transmission at the expense of the output angular velocity. If excess output torque is present it is transformed into an additional increment of output angular velocity within the mechanism's constraints. This transmission consequently acts as a mechano-inertial load matcher between a power source and its load. Since useful power is transmitted by means of applying angular and radial accelerations--both positive and negative--to the transmission's respective momentum storage links--via the links' mass properties, this transmission invention is conceived as an "inertial" transmission in contrast to other transmissions which are characterized as "geared", "friction", "traction" and "hydraulic". Its uniqueness is the cyclical pumping, or transferring of momentum, from a power source into a dynamic link storage unit from where it is pumped or transferred into an output link along with its associated rotational kinetic energy so as to deliver infinitely-varying ratios of torque and angular velocity in accordance with the changing requirements of the load.
It is well known that angular momentum L, when conserved in a mass system, causes the system's angular velocity .omega. to change inversely with the system's moment of momentum or, synonomously, moment of inertia I because of the following mathematical relationships of these parameters to one another: L=I.omega., .omega.=L/I and I=L/.omega.. The rotational kinetic energy developed in a rotating system is expressed as 1/2I.omega..sup.2. Because the rotational kinetic energy is transmitted through the transmission at varying rates with respect to time, the transmission transmits power at various demands. This rotational power transmission entity consists of two parametric components in multiplicative relationship. These components are torque and angular velocity. The primary function of any automotive transmission should be defined as the optimum apportionment of these two components accompanied by a minimum of power friction losses. The apportioning of these two components, or their ratio mix, must be responsive to the immediate load demand and power source capabilities in order to achieve an optimum state of function. All present day automotive transmissions, whether automatic or manual, fall short of such optimum performance values because of being limited in this apportionment capability both with respect to the ratio range and to the finiteness of the ratios provided. In those transmissions where the available ratios are the greatest, while being severly limited in apportionment range--namely automatic transmissions--the efficiency of power transmission is, almost without exception, the worst due to fluid friction losses.
The utilization of angular momentum in this transmission for the purpose of overcoming such inefficiencies of frictional losses, as found in present day transmissions, can best be understood by a general discussion relating to angular momentum. A frequently cited example of momentum conservation is that of a skater pirouetting on one skate tip who, upon decreasing his moment of inertia I by bringing his arms to his sides, increases his angular velocity .omega.. Not so familiar is the consideration of the frictional effect between the skate tip and the ice surface during the pirouetting movement. Because of this opposing torsional stress M, the skater's angular momentum L is not completely conserved, but is nearly so, during the short time interval of arm lowering. For simplicity, windage losses are neglected. Because of the angular momentum L not being totally conserved, due to the presence of the torsional stress M, this transferring of angular momentum L to the ice results in an infinitesimal change in the angular velocity of the earth's mass. The angular momentum loss, .DELTA.L, by way of torsional stress transference from one momentum system to another, then causes the cited momentum conservation to be only partially applicable to the skater. Torque arises from the time-rate-of-change of angular momentum L. M=Id.omega./d.tau.=d(I.omega.)/d.tau.=dL/d.tau. or, the resultant external torque equals the rate-of-change of angular momentum. Consequently Md.tau.=dL which, when integrated over a time interval, e.g., from .tau..sub.1 to .tau..sub.2, results in an angular impulse of torque equal to a change in angular momentum as follows: ##EQU1## Thus, the greater the skate's torque M against the ice the lesser is the increase of the skater's angular velocity .omega. for a given reduction of the skater's moment of inertia I. From this it is understood that, in the spirit of the present invention, a reduction of the moment of inertia I can result in both an increase in angular velocity .omega. and in torque M, the magnitudes of both angular velocity .omega. and torque M bearing an inverse relationship of I where angular momentum L is present.
An even lesser appreciated aspect of momentum conservation is that momentum is transferred from one mass system to another by any stress vector entity interacting between them. For example, there can be six degrees of stress vectors as there can be six degrees of motion vectors. These degrees are in addition to compound applications of the stress vectors. Such stress vector forces arise from physical contact between bodies or from action-at-a-distance forces such as those which arise from gravitational and electromagnetic fields. In completing this general discussion of angular momentum conservation, it is then understood that, if the pirouetting skater raises his arms, the moment of inertia I will be increased resulting in a reduction of the skater's angular velocity .omega.. But if additional angular momentum L is introduced to the skater's body concomitantly as his moment of Inertia I is increased, for example through torque application by means of a shaft attached to a helmet top which, in turn, is strapped to the skater's head, then this angular velocity .omega. can be lessened in its reduction, held constant, or actually increased in value dependent upon the torque and power characteristics of the power source.
With respect to the structure of the present invention, a transmission unit is provided including a number of movable inertial masses which cyclically change their radii-of-gyration from maximum-to-minimum and from minimum-to-maximum values relative to a reference axis of rotation. This transmission unit is coupled to a rotatable output shaft. If this shaft is stationary--as the movable inertial masses transit through their half-cycle of changing from their maximum radii-of-gyration to their minimum, e.g., as the brake on a vehicle is released and the accelerator depressed in automotive application during vehicular start-up--a maximum torque is exerted on the rotatable but initially stationary output shaft. That it is possible for the movable inertial masses to continuously orbit or travel about a reference point so as to cyclically traverse from positions of maximum-to-minimum-to-maximum radii-of-gyration, while the rotatable output shaft experiences torque impulses therefrom, as its angular velocity remains zero, such a kinematic linkage interaction is one of the novel features of this invention. Consequently, a change in torque and/or angular velocity is applied to the output shaft, depending upon the characteristics of the load coupled to the transmission unit. Torque and angular velocity are inversely and linearly related such that they are automatically proportioned or "rationed" in an infinite step or manner to provide optimum torque and angular velocity to the output shaft dependent upon the load. The magnitudes of such apportionment components, of course, also reflect the power characteristics of the power unit to which the transmission's input shaft is coupled.
Although various coupling mechanisms have been devised relating to the coupling of energy from a driving source to a driven source, these coupling mechanisms do not automatically and infinitely convert angular velocity to torque and torque to angular velocity using the angular momentum of dynamic solid masses present within the system. Rather, much of the prior art devices are limited to slip clutch arrangements which are not torque converters. Other prior art mechanisms are transmission devices which do include masses for undergoing a radius of gyration change. However, these mechanisms utilize centrifugal and frictional forces for operation, unlike the present invention which minimizes friction losses and utilizes the conservation of angular momentum for apportioning the necessary torques and angular velocities but not centrifugal forces thereof. In this regard, unlike the present invention wherein inertial masses are continuously oscillated to provide a cyclic radius-of-gyration change, prior known devices include non-continuously oscillating masses to effect fixed step changes between angular velocity and torque.